The Upper Devonian Sandstone aquifer of Fife

The Devonian sandstone aquifer of Fife has long been recognised as one of the most important hydrogeological units in Scotland. Its importance was first acknowledged by Earp and Eden (1961), and the aquifer was later described by Foster et al (1976). Data were subsequently gathered together in map form (BGS, 1986) but little analysis of the aquifer was carried out other than a dissertation prepared by Barker (1981), occasional reports on specific issues such as nitrate pollution (e.g. Frost and Sargent, 1993; MacDonald, 1993; Ball, 1994), and the preparation of the 1: 100 000 scale Aquifer Vulnerability Map of Fife (SEPA, 1999). The aquifer currently supplies some 20 Ml/d during the winter, rising to 40 Ml/d in the summer months, when irrigation boreholes are put into use. Groundwater provides an important back up to public water supplies, particularly during dry years when river abstraction is restricted. Despite this, relatively little is known about the overall renewable resource potential of the aquifer. It is also only in recent years that means of safeguarding groundwater from pollution have been investigated in any detail. Renewed interest in the aquifer is now being driven on two fronts. The first is that the East of Scotland Water Authority (ESWA) needs to expand its source provision due to increasing demand. The second is that the Scottish Environment Protection Agency (SEPA) needs to look more closely at the aquifer potential if in the future groundwater abstraction licensing is introduced in significant aquifers (Robins and Ball, 1998). In addition, the requirements of the proposed EU Water Framework Directive indicate that a greater understanding of the aquifer and the sources it supplies will be needed in order to implement properly integrated surface and groundwater management on a catchment basis. With these goals in mind, the East of Scotland Water Authority, Scottish Environment Protection Agency and NERC have jointly commissioned this preliminary study of the Eden valley aquifer

Post-acute COVID-19 neuropsychiatric symptoms are not associated with ongoing nervous system injury

A proportion of patients infected with severe acute respiratory syndrome coronavirus 2 experience a range of neuropsychiatric symptoms months after infection, including cognitive deficits, depression and anxiety. The mechanisms underpinning such symptoms remain elusive. Recent research has demonstrated that nervous system injury can occur during COVID-19. Whether ongoing neural injury in the months after COVID-19 accounts for the ongoing or emergent neuropsychiatric symptoms is unclear. Within a large prospective cohort study of adult survivors who were hospitalized for severe acute respiratory syndrome coronavirus 2 infection, we analysed plasma markers of nervous system injury and astrocytic activation, measured 6 months post-infection: neurofilament light, glial fibrillary acidic protein and total tau protein. We assessed whether these markers were associated with the severity of the acute COVID-19 illness and with post-acute neuropsychiatric symptoms (as measured by the Patient Health Questionnaire for depression, the General Anxiety Disorder assessment for anxiety, the Montreal Cognitive Assessment for objective cognitive deficit and the cognitive items of the Patient Symptom Questionnaire for subjective cognitive deficit) at 6 months and 1 year post-hospital discharge from COVID-19. No robust associations were found between markers of nervous system injury and severity of acute COVID-19 (except for an association of small effect size between duration of admission and neurofilament light) nor with post-acute neuropsychiatric symptoms. These results suggest that ongoing neuropsychiatric symptoms are not due to ongoing neural injury

Magnetostratigraphic dating: Insights to Late Cenozoic deposition and dolomitization of Little Bahama Bank

Magnetostratigraphic dating of a transect of cores across Little Bahama Bank (LBB) provides refined insight into timing and anatomy of platform deposition since late Miocene. Age-dating of four cores, with biostratigraphic tie-points, shows a gently northward dipping platform from late Miocene to about mid-Pleistocene (0.73 Ma) as a result of higher growth/accumulation of the southwestern platform margin. Magnetostratigraphic dating coupled with Sr-isotope ages from LBB dolomites significantly improves the late Cenozoic depositional/diagenetic framework. Dolomitization episodes at about 2.2-3.4 and 1.6 Ma correspond with a prolonged period of subaerial exposure and formation of large aquifer systems and perhaps providing a mechanism to pump dolomitizing fluids (seawater) through the platform. A distinct northward slope of the dolomite may be explained by either: (1) a northward-dipping platform top, which supported different aquifer levels during fluctuating sea level lowstand events, or (2) the thickness of the freshwater lens which in turn is controlled by differences in permeability and platform slope between the northern and southern margins

Late Neogene planktonic foraminifera of the Cibao Valley (northern Dominican Republic): Biostratigraphy and paleoceanography

An assemblage of planktonic foraminifera is described from 125 samples taken from the Cercado, Gurabo, and Mao Formations in the Cibao Valley, northern Dominican Republic. The primary objectives of this study are to establish a biochronologic model for the late Neogene of the Dominican Republic and to examine sea surface conditions within the Cibao Basin during this interval. The Cercado Formation is loosely confined to Zones N17 and N18 (∼ 7.0–5.9 Ma). The Gurabo Formation spans Zones N18 and N19 (∼ 5.9–4.5 Ma). The Mao Formation is placed in Zone N19 (∼ 4.5–3.6 Ma). Changes in the relative abundances of indicator species are used to reconstruct sea surface conditions within the basin. Increasing relative abundances of Globigerinoides sacculifer and Globigerinoides ruber, in conjunction with a decreasing relative abundance of Globigerina bulloides, suggests the onset of increasing sea surface temperature and salinity in conjunction with diminishing primary productivity at ∼ 6.0 Ma. Abrupt increases in the relative abundances of G. sacculifer and G. ruber at ∼ 4.8 Ma suggest a major increase in sea surface temperature and salinity in the early Pliocene. The most likely mechanism for these changes is isolation of the Caribbean Ocean through progressive restriction of Pacific–Caribbean transfer via the Central American Seaway. Periods of high productivity associated with upwelling events are recorded in the upper Cercado Formation (∼ 6.1 Ma) and in the middle Mao Formation (∼ 4.2 Ma) by spikes in G. bulloides and Neogloboquadrina spp. respectively. The timing of major increases in sea surface salinity and temperature as well as decreasing productivity (∼ 4.8 Ma) and periods of upwelling (∼ 6.1and 4.2 Ma) in the Cibao Basin generally corroborate previously suggested Caribbean oceanographic changes related to the uplift of Panama. Changes in sea surface conditions depicted by paleobiogeographic distributions in the Cibao Basin suggest that shoaling along the Isthmus of Panama had implications in a shallow Caribbean basin as early as 6.0 Ma. Major paleobiologic changes between ∼ 4.8 and 4.2 Ma likely represent the period of final closure of the CAS and a nearly complete disconnection between Pacific and Caribbean water masses. This study illustrates the use of planktonic foraminifera in establishing some paleoceanographic conditions (salinity, temperature, productivity, and upwelling) within a shallow water basin, outlining the connection between regional and localized oceanographic changes

Rapid growth rates of syndepositional marine aragonite cements in steep marginal slope deposits, Bahamas and Belize

Growth rates of marine botryoidal aragonite cements from steep (35-45[degree]) marginal slope deposits in the Bahamas and Belize have been determined by accelerator mass spectrometer radiocarbon dating of samples taken at the base and top of individual botryoids. The pore-filling cements, which range from approximately 11,000-13,000 years old, grew at average rates of 8-10mm/100 yr with maximum rates > 25mm/100 yr. Radiocarbon dating of coexisting skeletal components indicates that cementation was syndepositional. Microsampling transects across individual botryoids for stable-isotope analyses show little variation in [delta][sup 31]C and [delta][sup 18]O, supporting the conclusion that cementation was extremely rapid. Although the cements show a progressive depletion in isotopic composition of approximately 1[per thousand]([delta][sup 13]C) and 2[per thousand]([delta][sup 18]O) from 13 ka to 11 ka, the average variation ([delta][sub 1]) within individual pore-filling cements, ranging in size 2 mm to 32 mm (bottom to top), was 0.11[per thousand]([delta][sup 13]C) and 0.14[per thousand]([delta][sup 18]O). Results of this study provide the first quantitative data on growth rates of marine carbonate cements in a marginal slope environment. The data indicate that marginal slope deposits may lithify within several tens of years and suggest that geologically instantaneous cementation may be critical in stabilizing steep carbonate slope deposits at or above angles of repose